Predator functional response in mathematical models compared to the zooplankton functional response in a lake ecosystem

The problem of predator interference and the associated choice between two types of functions describing the functional response in mathematical modeling of population dynamics are widely discussed. It is the choice between predator-dependent and prey-dependent functions. Here we present the results of comparing a wide range of the functions describing the functional response, which are used in modeling trophic interactions, with the functional response that is characteristic of interactions between phytoplankton and zooplankton populations in the ecosystem of the Naroch Lakes (Belarus). We apply the knowledge-and-data-driven, or KDD, approach, which allows us to use the results of the monitoring of the Naroch Lakes ecosystem, to identify the time-dependent functional response in each of the reservoirs of this ecosystem. The KDD approach provides for direct input of monitoring data into the mathematical description of population dynamics. As a result, we show that predator-dependent functional responses best match the environmental processes in the ecosystem of the Naroch Lakes. At the same time, we have identified predator-dependent functions that meet the monitoring data even worse than prey-dependent functions.